The problem of getting labels to detach from containers is one of long standing, and a related problem is one of removing the detached labels from the tanks containing the washing solution. The washing solution has traditionally been hot caustic for attacking the glue used to affix the labels and concurrently effecting sterilization of the containers preparatory to filling.
An early effort to solve the problem of label detachment and removal was made by the use of oscillating paddles located in one or more tanks in the upper zone of the washing solution therein for the express purpose of sloshing the solution through the conveying pockets in which the containers were placed for the travel through the washer apparatus. Not much good effect was accomplished by this approach due to the unrecognized events that occured when the paddle was oscillated between the deflector or guide means necessary to keep the containers in the conveyor pockets. Accordingly the detached labels merely oscillated in rhythm with the paddle and often time hung on the deflectors or returned to the conveyor where they become reapplied to the containers. The problem has remained acute due to the large number of labels found to be present in the tanks at or near the discharge of the containers from the washer apparatus.
Certain early usage of oscillating paddles in the upper zone of the washing solution is seen in the Meyer Dumore Bottle Cleaner of Geo. J. Meyer Manufacturing Co., Milwaukee, Wis., or Liquid Carbonic Company Ltd, London, both of which are illustrated in the May 1953 Schweizer Brauerei-Rundschau, Swiss Review of Breweries. Another use of oscillating paddles is found in Babunovic et al U.S. Pat. No. 3,162,204, granted Dec. 22, 1964. On study of these washers it can be appreciated that as the paddle oscillates and moves from one extreme position to the other the washing solution curls around the lower edge and rises into the low pressure zone directly behind the paddle. The result is that the washing solution is caused to oscillate in the container pockets so that the detached labels also oscillate and do not make rapid transfer to places where collection can occur. Also, these prior art arrangements made the whole tank a label collector which makes the job of collecting the labels more difficult as they are spread over a large area, and a proportion of the labels are deposited again on the container.